You can use the text tool. You can also write a Photoshop Script to retrieve the EXIF metadata date and stamp it onto your document.

An script is included in my crafting action package to stamp some exif data on to an image and another to open Goolemap on the location the image was shot if there geotag information in the EXIF data. StampEXIF.jsx and GoogleManGPS.jsx

The stampexif script was created to be used in actions. you record a step File>scripts>stampexif. It just a step and your action could be batched ab all your images stamped with exif date. The script adds the text layer. The action can then style and position that added text layer.